This research examines biological and psychological relationships during adolescence. Children and adolescents are studied through the pubertal period. Participants are male and female 9- to 14-year-olds and their parents. At three times of measurement, six months apart, participants are evaluated for stage of pubertal development by blood samples for gonadotropins, gonadal steriods, and adrenal androgens as well as by a physical examintion to determine their Tanner stage. Psychological assessments include standardized psychological tests and systematic observation of parent-child interactions.